Liquid Water Removal Apparatus

ABSTRACT

Liquid water removal apparatus that removes residual liquid water in a fluid conducting system by vaporizing the residual liquid water and drawing the vaporized water from the fluid conducting system. A vacuum pump (a) reduces the atmospheric pressure in the fluid conducting system to vaporize residual liquid water in the fluid conducting system, (b) draws from the fluid conducting system vaporized water, and (c) partially condenses the vaporized water drawn from the fluid conducting system. Vaporized water is conducted from the vacuum pump to a first water vapor condenser where vaporized water is condensed and residual vaporized water is conducted from the first water vapor condenser to a second water vapor condenser where the residual vaporized water received from the first water vapor condenser is condensed.

FIELD OF THE INVENTION

The present invention relates, in general, to the removal of residual liquid water in fluid conducting systems and, in particular, to liquid water removal apparatus that removes residual liquid water in fluid conducting systems by vaporizing the residual liquid water, drawing the vaporized water from the fluid conducting system, and condensing the vaporized water.

BACKGROUND

Pre-action and dry fire suppression sprinkler manifold systems require periodic testing to verify water fill integrity. Complete draining of such systems is difficult, and often not possible, leaving water pools inside steel header pipes and pendants. Oxidation occurs within the manifold that nourishes naturally occurring microbes. Eventually, microbe colonies form at the water/dry interface that appear as rust deposits inside the steel pipe. Over time, the microbes secrete acids that accelerate oxidation rates underneath their colonies leading to through-holes. Hole formation occurs randomly and requires immediate repair adding to the complexity and expense of maintaining such systems.

Until now, treatment options have been limited. An immediate fix involves cutting out and replacing damaged manifold pipes. This strategy works when hole formation frequency is low and affected areas are not in critical locations. However, as microbe colonies mature, hole formation accelerates making this option increasingly expensive. Damage to surrounding areas associated with discolored water spray and sprinkler system service interruptions reduce the appeal of this solution.

Biocide treatments are available where the manifold is flooded with a toxic solution and drained. Application of toxic materials into building systems and disposal of toxic effluent has been objectionable. Whenever water is reintroduced, as when annual validation testing occurs, the biocide treatment must be repeated.

As a last resort, sprinkler system replacement has occurred when no other means of controlling hole formation have worked. The exceptional expense and inconvenience associated with replacement buys more time but does not fix the problem.

As a result, various forms of liquid water removal apparatus have been developed, whereby residual liquid water in the sprinkler systems and other fluid conducting systems is removed periodically in an attempt to eliminate or greatly lessen the adverse effects, described above, of oxidation of residual water in the sprinkler systems. Generally, the liquid water removal apparatus and services that are available at the present time fail to satisfy the concurrent requirements of high level effective and adequate liquid water removal and cost-effective liquid water removal.

SUMMARY

Liquid water removal apparatus, constructed in accordance with the present invention, includes a vacuum pump for reducing atmospheric pressure in a fluid conducting system to vaporize residual liquid water in the fluid conducting system, drawing into the vacuum pump from the fluid conducting system vaporized water, and partially condensing vaporized water drawn into the vacuum pump. The vacuum pump has an inlet through which vaporized water is drawn into the vacuum pump from the fluid conducting system, a sump for collecting liquid water, and an outlet through which liquid water in the sump is withdrawn from the vacuum pump. The liquid water removal apparatus also has a first water vapor condenser for receiving vaporized water from the vacuum pump, condensing vaporized water received from the vacuum pump, and discharging water condensed by the first water vapor condenser. In addition, the liquid water removal apparatus has a second water vapor condenser for receiving residual water vapor from the first water vapor condenser, condensing residual water vapor received from the first water vapor condenser, and discharging water condensed by the second water vapor condenser.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a first embodiment of liquid water removal apparatus constructed in accordance with the present invention

FIG. 2 is a schematic diagram of a second embodiment of liquid water removal apparatus constructed in accordance with the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring to the FIG. 1 embodiment of the present invention, liquid water removal apparatus, constructed in accordance with the present invention, includes a vacuum pump 10 that (1) reduces the atmospheric pressure in a fluid conducting system, such as a fire suppression sprinkler system represented by a manifold 12 in which residual water is present, to vaporize residual liquid water in the fluid conducting system, (2) draws from the fluid conducting system vaporized water represented by an arrow 14, and (3) partially condenses vaporized water drawn into the vacuum pump. It will be apparent that the present invention can be used to remove residual liquid water from other fluid conducting systems, such as petroleum pipe lines and gas pipe lines that are subjected to hydrostatic testing for integrity and thereby are susceptible to residual liquid water.

Vacuum pump 10, which can be an oil-sealed vacuum pump such as Model HVC100A sold by HullVac Pump Corporation, has an inlet 10 a through which vaporized water is drawn into the vacuum pump from the fluid conducting system, a sump 10 b for collecting liquid water, and an outlet 10 c through which liquid water in the sump is withdrawn from the vacuum pump, as represented by an arrow 16, and discharged into a suitable container. Vacuum pump 10 partially condenses the vaporized water drawn from the fluid conducting system and this condensate is collected in sump 10 b. Sump 10 b can be a specially arranged compartment in vacuum pump 10 in which liquid water is collected or simply be the lower region of the housing of the vacuum pump.

The FIG. 1 liquid water removal apparatus also has a first water vapor condenser 18 for receiving vaporized water from vacuum pump 10, for example, via a conduit 20. Vaporized water received from vacuum pump 10 is condensed by first water vapor condenser 18 and the condensed water vapor is supplied to vacuum pump 10, for example, via a conduit 22. When vacuum pump 10 is an oil-sealed vacuum pump, first water vapor condenser 18 may be a coalescing filter, such as Model HDL-PSG 860/1-200HC sold by Solberg Manufacturing Co. A check valve 24 of conventional construction and operation is fitted into conduit 22 to prevent the flow of a water/oil mixture from vacuum pump 10 to first water vapor condenser 18 when the water/oil mixture pressure in the vacuum pump rises to a predetermined level that might cause such an undesirable flow. It will be understood that other fluid-sealed and non-fluid sealed vacuum pumps can serve as vacuum pump 10.

A solenoid valve of conventional construction and operation, controlled by a vacuum gage 25 of conventional construction and operation, can be substituted for check valve 24. Vacuum gage 25 serves as an inlet sensing means that senses the pressure of the vaporized water drawn from the fluid conducting system and when this pressure exceeds a predetermined level, the solenoid valve, substituted for check valve 24, closes to prevent an undesirable flow of a water/oil mixture from vacuum pump 10 to first water vapor condenser 18.

The FIG. 1 liquid water removal apparatus further includes a second water vapor condenser 26 for receiving, for example, via a conduit 28, residual water vapor from first water vapor condenser 18 which is condensed by the second water vapor condenser. This condensed water is conducted, via a conduit 30, for discharge to a suitable container with the liquid discharged from vacuum pump 10 through outlet 10 c. As an alternative, the condensate in second water vapor condenser 26 can be discharged from this condenser via a conduit 31, shown in dashed lines, into conduit 24 for discharge from vacuum pimp 10 with liquid water from sump 10 b. As represented by an arrow 32, second water vapor condenser 26 exhausts saturated air to the atmosphere. Second water vapor condenser 26 may be Model FP5X12-12 sold by GEA Flat Plate Inc.

The FIG. 1 liquid water removal apparatus preferably includes heat exchanging means for enhancing the performance of second water vapor condenser 26 by maintaining the temperature of the second water vapor condenser in a predetermined temperature range. The heat exchanging means include a fluid reservoir 33 in thermal contact with second water vapor condenser 26 and contains a coolant fluid, such as water. The heat exchanging means also include a coolant fluid pump 34, such as Red Fox Model NRE-22 sold by Pex Supply, for drawing the coolant fluid from fluid reservoir 33, a radiator to which coolant fluid is conducted from the coolant fluid pump for radiating heat in the coolant fluid to the atmosphere and returning the coolant fluid to the fluid reservoir, and a fan for cooling the radiator. The radiator and fan may be combined in a single unit, identified by reference numeral 36, that includes, for example, Radiator Part # CU1444 sold by Rock Auto and Fan Part # 5160904 sold by Speedy Car Parts.

The FIG. 1 liquid water removal apparatus also includes sump liquid water level sensing means for sensing the level of the liquid water in sump 10 b of vacuum pump 10 and sump control means, responsive to the sump liquid water level sensing means, for selectively controlling the flow of liquid water from outlet 10 c of the vacuum pump to permit withdrawal of the liquid water in the sump of the vacuum pump and discharge of this liquid water into a suitable container when the level of the liquid water in the sump reaches a predetermined level. The sump liquid water level sensing means may be a liquid level sensor 38, such as Part # M3784-110 sold by Madison Company, suitably disposed in vacuum pump 10. The control means for selectively controlling the flow of liquid water from outlet 10 c of vacuum pump 10 to permit withdrawal of the liquid water in the sump of the vacuum pump may include a valve 40, of conventional construction and operation, that is opened and closed in response to the output of liquid level sensor 38. When vacuum pump 10 is an oil-sealed vacuum pump and first water vapor condenser 18 is a coalescing filter, liquid level sensor 38 is so disposed in the vacuum pump that the predetermined level of liquid water in sump 10 b, by which liquid water is permitted to be withdrawn, is below a film of oil that extends over the liquid water, so that oil is not withdrawn and discharged with liquid water from the sump. It will be apparent that outlet 10 c of vacuum pump 10 may be arranged to be directly controlled by liquid level sensor 38 to permit withdrawal and discharge of liquid water from sump 10 b.

Uncontrolled entry of liquid water into vacuum pump 10 (i.e., “flooding” of the vacuum pump) can cause severe damage. Consequently, the FIG. 1 liquid water removal apparatus preferably includes means for protecting against flooding of vacuum pump 10. Such means include inlet sensing means for sensing the passage of liquid water from the fluid conducting system to vacuum pump 10 and inlet control means, responsive to the inlet sensing means, for selectively controlling the flow of liquid water from the fluid conducting system to inlet 10 a of the vacuum pump to prevent passage of undesirable amounts of liquid water from the fluid conducting system to the vacuum pump when the flow of the liquid water from the fluid conducting system exceeds a predetermined level.

The inlet sensing means may be a fluid flow sensor 42, such as Part # LVU-152-R sold by Omega Engineering. For the embodiment of the invention illustrated in FIG. 1 and being described, the control means for selectively controlling the flow of liquid water from the fluid conducting system to inlet 10 a of vacuum pump 10 include a plurality of valves 44, 46, 48, and 50, all of conventional construction and operation, that operate in response to the output of fluid flow sensor 42. Valves 44 and 50 are closed and valves 46 and 48 are opened when the flow of liquid water from the fluid conducting system that is sensed by fluid flow sensor 42 exceeds a predetermined level and vacuum pump 10 is to be isolated from the fluid conducting system.

Valve 50 serves to isolate the entire liquid water removal apparatus from the fluid conducting system. With both valve 44 and valve 50 closed and valve 46 open, liquid water that has already left the fluid conducting system before the closing of valve 50 is blocked by closed valve 44 from entering vacuum pump 10 and is drained through open valve 46 to a suitable container. Valve 48 serves to vent the atmosphere when valve 44 is closed and valve 46 is open.

After the liquid water has been drained and fluid flow sensor 42 no longer senses a flow of liquid water that exceeds the predetermined level that caused isolation of vacuum pump 10, valves 44 and 50 are opened by the fluid flow sensor. Valves 46 and 48, opened by fluid flow sensor 42, remain open for a predetermined time period that is based on the anticipated time required to drain the expected accumulation of liquid water prior to the closing of valve 50. Upon expiration of this predetermined time period, valves 46 and 48 close. With valves 44 and 50 opened and valves 46 and 48 closed, the liquid water removal apparatus resumes normal operation.

The FIG. 1 liquid water removal apparatus preferably includes a filter or trap 52 of conventional construction and operation for collecting solid particulate matter drawn from the fluid conducting system and preventing this solid particulate matter from entering vacuum pump 10.

FIG. 2 is a schematic diagram of a second embodiment of liquid water removal apparatus constructed in accordance with the present invention. The FIG. 2 embodiment, in many respects, is similar to the FIG. 1 embodiment. Therefore, components, common to the two embodiments, have been given the same reference numerals and a detailed description of the functions and operations of those components, common to the two embodiments, is not repeated.

In the FIG. 2 embodiment of the present invention, a fluid flow sensor 54, similar to fluid flow sensor 42 in FIG. 1, is located in trap 52 and serves as an inlet sensor that senses the passage of liquid water from the fluid conducting system. Fluid flow sensor 54 senses when the flow of liquid water from the fluid conducting system to vacuum pump 10 exceeds a predetermined level. When the flow of liquid water from the fluid conducting system exceeds this predetermined level, a valve 56, similar to valve 50 in FIG. 1, is closed by fluid flow sensor 54 to isolate vacuum pump 10 from the fluid conducting system. The closing of valve 56, in turn, activates a variable speed drive 58, such as Model SKB3400759 sold by Emerson Industrial Automation, that, in turn, reduces the speed of vacuum pump 10 until fluid flow sensor 54 senses that liquid water that has accumulated prior to the closing of valve 56 has been ingested by vacuum pump (i.e., collected in sump 10 b of the vacuum pump). When this condition is sensed, fluid flow sensor 54 opens valve 56 which, in turn, inactivates variable speed drive 58 and permits vacuum pump 10 to operate independent of the influence of the variable speed drive. The liquid water removal apparatus then resumes normal operation.

The foregoing illustrates some of the possibilities for practicing the present invention. Many other embodiments are possible within the scope and spirit of the present invention. It is, therefore, intended that the foregoing description be regarded as illustrative rather than limiting, and that the scope of the present invention is given by the appended claims together with their full range of equivalents. 

1. Liquid water removal apparatus, adapted for connection to a fluid conducting system, said apparatus comprising: a vacuum pump: (a) for: (1) reducing atmospheric pressure in a fluid conducting system to vaporize residual liquid water in the fluid conducting system, (2) drawing into said vacuum pump from the fluid conducting system vaporized water, and (3) partially condensing vaporized water drawn into said vacuum pump from the fluid conducting system, and (b) having: (1) an inlet through which vaporized water is drawn into said vacuum pump from the fluid conducting system, (2) a sump for collecting liquid water, and (3) an outlet through which liquid water in said sump is withdrawn from said vacuum pump; a first water vapor condenser for: (a) receiving vaporized water from said vacuum pump, (b) condensing vaporized water received from said vacuum pump, and (c) discharging water condensed by said first water vapor condenser; and a second water vapor condenser for: (a) receiving residual water vapor from said first water vapor condenser, (b) condensing residual water vapor received from said first water vapor condenser, and (c) discharging water condensed by said second water vapor condenser.
 2. Liquid water removal apparatus according to claim 1 further including: (a) sump liquid water level sensing means for sensing the level of the liquid water in said sump of said vacuum pump; and (b) sump control means, responsive to said sump liquid water level sensing means, for selectively controlling the flow of liquid water from said outlet of said vacuum pump to permit withdrawal of the liquid water in said sump of said vacuum pump.
 3. Liquid water removal apparatus according to claim 1 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) inlet control means, responsive to said inlet sensing means, for selectively controlling the flow of liquid water from the fluid conducting system to said inlet of said vacuum pump.
 4. Liquid water removal apparatus according to claim 2 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) inlet control means, responsive to said inlet sensing means, for selectively controlling the flow of liquid water from the fluid conducting system to said inlet of said vacuum pump.
 5. Liquid water removal apparatus according to claim 1 wherein: (a) said vacuum pump is an oil-sealed vacuum pump, and (b) said first water vapor condenser is a coalescing filter.
 6. Liquid water removal apparatus according to claim 5 further including: (a) sump liquid water level sensing means for sensing the level of the liquid water in said sump of said vacuum pump, and (b) sump control means, responsive to said sump liquid water level sensing means, for selectively controlling the flow of liquid water from said outlet of said vacuum pump to permit withdrawal of the liquid water in said sump of said vacuum pump.
 7. Liquid water removal apparatus according to claim 5 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) inlet control means, responsive to said inlet sensing means, for selectively controlling the flow of liquid water from the fluid conducting system to said inlet of said vacuum pump.
 8. Liquid water removal apparatus according to claim 6 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) inlet control means, responsive to said inlet sensing means, for selectively controlling the flow of liquid water from the fluid conducting system to said inlet of said vacuum pump.
 9. Liquid water removal apparatus according to claim 1 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) vacuum pump speed control means, responsive to said inlet sensing means, for selectively controlling the speed of said vacuum pump in accordance with the flow of the liquid water from the fluid conducting system to said vacuum pump.
 10. Liquid water removal apparatus according to claim 5 further including: (a) inlet sensing means for sensing the passage of liquid water from the fluid conducting system to said vacuum pump, and (b) vacuum pump speed control means, responsive to said inlet sensing means, for selectively controlling the speed of said vacuum pump in accordance with the flow of the liquid water from the fluid conducting system to said vacuum pump.
 11. Liquid water removal apparatus according to claim 4 further including heat exchanging means: (a) for maintaining the temperature of said second water vapor condenser in a predetermined temperature range, and (b) including: (1) a fluid reservoir in thermal contact with said second water vapor condenser and containing a coolant fluid, (2) a coolant fluid pump for drawing the coolant fluid from said fluid reservoir, (3) a radiator to which coolant fluid is conducted from said coolant fluid pump for radiating heat in said coolant fluid to the atmosphere and returning the coolant fluid to said fluid reservoir, and (4) a fan for cooling said radiator.
 12. Liquid water removal apparatus according to claim 9 further including heat exchanging means: (a) for maintaining the temperature of said second water vapor condenser in a predetermined temperature range, and (b) including: (1) a fluid reservoir in thermal contact with said second water vapor condenser and containing a coolant fluid, (2) a coolant fluid pump for drawing the coolant fluid from said fluid reservoir, (3) a radiator to which coolant fluid is conducted from said coolant fluid pump for radiating heat in said coolant fluid to the atmosphere and returning the coolant fluid to said fluid reservoir, and (4) a fan for cooling said radiator.
 13. Liquid water removal apparatus according to claim 10 further including heat exchanging means: (a) for maintaining the temperature of said second water vapor condenser in a predetermined temperature range and (b) including: (1) a fluid reservoir in thermal contact with said second water vapor condenser and containing a coolant fluid, (2) a coolant fluid pump for drawing the coolant fluid from said fluid reservoir, (3) a radiator to which coolant fluid is conducted from said coolant fluid pump for radiating heat in said coolant fluid to the atmosphere and returning the coolant fluid to said fluid reservoir, and (4) a fan for cooling said radiator.
 14. Liquid water removal apparatus according to claim 2 further including heat exchanging means: (a) for maintaining the temperature of said second water vapor condenser in a predetermined temperature range, and (b) including: (1) a fluid reservoir in thermal contact with said second water vapor condenser and containing a coolant fluid, (2) a coolant fluid pump for drawing the coolant fluid from said fluid reservoir, (3) a radiator to which coolant fluid is conducted from said coolant fluid pump for radiating heat in said coolant fluid to the atmosphere and returning the coolant fluid to said fluid reservoir, and (4) a fan for cooling said radiator.
 15. Liquid water removal apparatus according to claim 1 further including means for supplying water condensed by said first water vapor condenser to said sump of said vacuum pump.
 16. Liquid water removal apparatus according to claim 15 further including means for supplying water condensed by said second water vapor condenser to said sump of said vacuum pump.
 17. Liquid water removal apparatus according to claim 4 further including means for supplying water condensed by said first water vapor condenser to said sump of said vacuum pump.
 18. Liquid water removal apparatus according to claim 17 further including means for supplying water condensed by said second water vapor condenser to said sump of said vacuum pump.
 19. Liquid water removal apparatus according to claim 8 further including means for supplying water condensed by said first water vapor condenser to said sump of said vacuum pump.
 20. Liquid water removal apparatus according to claim 19 further including means for supplying water condensed by said second water vapor condenser to said sump of said vacuum pump.
 21. Liquid water removal apparatus according to claim 14 further including means for supplying water condensed by said first water vapor condenser to said sump of said vacuum pump.
 22. Liquid water removal apparatus according to claim 21 further including means for supplying water condensed by said second water vapor condenser to said sump of said vacuum pump. 